Implement tracking of BUILD.gn files used to define target, toolchain or

tools/gn/scope_per_file_provider_unittest.cc

Index: tools/gn/scope_per_file_provider_unittest.cc
diff --git a/tools/gn/scope_per_file_provider_unittest.cc b/tools/gn/scope_per_file_provider_unittest.cc
index d016a1e1f5c975c78f093ea7e28099a110f8b1b4..c173ef0f19a809ec4af3cc501a522f91f4a33172 100644
--- a/tools/gn/scope_per_file_provider_unittest.cc
+++ b/tools/gn/scope_per_file_provider_unittest.cc
@@ -18,7 +18,7 @@ TEST(ScopePerFileProvider, Expected) {
 
   // Test the default toolchain.
   {
-    Scope scope(test.settings());
+    Scope scope(test.settings(), {});
     scope.set_source_dir(SourceDir("//source/"));
     ScopePerFileProvider provider(&scope, true);
 
@@ -36,10 +36,10 @@ TEST(ScopePerFileProvider, Expected) {
   // Test some with an alternate toolchain.
   {
     Settings settings(test.build_settings(), "tc/");
-    Toolchain toolchain(&settings, Label(SourceDir("//toolchain/"), "tc"));
+    Toolchain toolchain(&settings, Label(SourceDir("//toolchain/"), "tc"), {});
     settings.set_toolchain_label(toolchain.label());
 
-    Scope scope(&settings);
+    Scope scope(&settings, {});
     scope.set_source_dir(SourceDir("//source/"));
     ScopePerFileProvider provider(&scope, true);